Assassin's Creed Syndicate: London Wasn't Built in a Day

[Music] hello and welcome to my talk I'm going to talk about se syndicate and how we built the city so I'm Damian Tim would simply tool programmer at Ubisoft Quebec so first of all I will give you an idea general idea of the CTV build and the kind of game we did for a season decade so it's set in the Victorian London we built a city almost six square kilometers with almost 80 kilometres of drivable streets a little bit more than eight or nine intersections and we placed around 8,000 buildings I'm speaking about generic buildings because we include it excludes the landmarks train station factor isn't kind of big buildings so the presentation is going

to cover the different aspect of the solution we developed to build London instead of a simple list of topics let's watch a short video that introduced the London we built and all the features you

the only kind of weird but you get the idea of the feature we are so in addition of the video I'm going to talk about the user interface also you the interface they will evolve throughout the project for each subject I'm going to introduce the context explain what we did and some information about the post-mortem and feedback we get on these features so but first a little bit of franchise history we narrated all the technology from AC unity unity was set in Paris during the French Revolution the Australasian for city building was focused on house blocks they were organized there was sorry no organized traffic in Paris therefore the width of the street we had no real importance if a street was a little bit too large or too small it was only be perceived as organic by the

player the street we are likely attached in front of the building in a slightly downward slope until to the middle of the street and the AC needed tools only supported creating streets on the grid you can see the blue lines on the pictures so as consequence to it we're always a constraint in length or in angle to length and angle will not be affected flexible when we set a goal for associates indicate we decided very early that we wanted a more realistic street simulation meaning that we had to change away Street we handled compared to the previous assistant head game in simple world we wanted organized traffic for instance if you played an AC game before syndicate you might remember the street could have different widths and

the crowd always fill out the entire street we had to move the crowd simulation and circulation on the sidewalk the ethoxide engine called anvil had never been used to create any driving or racing game for and the team has no prior experience in this kind of game we knew we were going to need an easy way to iterate very late in production and easy way to edit it very late in production the last goal was to reuse as much as possible the IC unity technology for obvious reasons so in the franchisor grow the ground wealth usually manually created by artists for a season decade since we needed to enforce some very strict Street metrics for the driving experience we decided to have and to generate all the street measures both matically we started by using debug

displayed to prototype all the feature we wanted let's me let me show you a quick video of the prototyping phase without audio this time and the beginning at we are going to see education after intersection and our happen to attend to fill the AC unity solution on the whole network not good okay sorry trying to fix it okay it should work no okay so that's the debug display intersection so remember it's only in debug display so that one network that the building so in the last

frame of the video we try to fit the AC unity for the Paris house block on the new street we just created highlighted in blue house blocks and as you can see the orange arrow is pretty white offset between the building location and the edge of the street this is due to the strong anger enforcement of the AC unity technology we could on 4th Street to have to be at certain angle but we realized pretty quickly that if we process that way any change in a city result will altering much more as well in tundle we would have a domino effect that will spread addition point and in the fabric of the map as you can imagine this content was pretty drastic and we needed to get rid of it I will show you later how we managed to other with this but keep it in the back of your mind

after our first obtained in using double display we started looking into what our mesh and collision generation here is a quick video of the first time we were able to drive on the street so it's of course it's in debug displayed programmer art but this is real geometry generated so it's a first time wearable to drive the physician we settled for the hotmail generation is Baden slices small chunks of old from different sizes carefully polished by artists to generate the street from any lengths we calculate the best combination of slices to approximate the length and stretch all to apply a little bit to achieve the desired length during this process we also handled slopes if one end of the

treat is higher than the other for the intersection we created unique slices for each type of intersection to reduce the number of intersection we were able to move the extremity of the street from police or - 50 degrees so if we take top view of the street very schematic one it's a t-shape intersection and we could move the end of the street in the red cone and it will be the same for all other street entry at the end of the project we added curvature are very small curvature in the center of the street this picture is this picture is very exaggerated the curvature is very big but will you get the idea to conclude on the street merging action the final generated revealed by the

effective factor in terms of graphical fidelity the small stretching of meshes was not noticeable at all however we had made the street match the narration very easy and we did not do anything for the lot besides the street meshes it was a major production issue on one side we made sure it was very easy to move the street around and to iterate fast on driving but each time we move a street someone had to redo the ground around it the intersection we have very tedious to create we had even with a small angle collection so prefer my name is 50-degree we were we had to create more than 100 intersections and at the end because everything was generated it was very easy to add the curvature let when

we tackle the next big challenge creating the building placed along around the whole network we went building London we had to account for some major iconic element of the city the first is you can see in this design document the building have not always the same depth it's an iconic element and you can create some interesting park or situation at the back of the building so we wanted to reproduce that in our version of London in London we have a lot of pedestrian back alleys who allow people to work from side wall to the courtyard some time with overpass and another iconic element are the what in front of some buildings and we also try to reuse the modular solution created by unity

building a split in multiple parts it being a key element of the building the front as you will expect open on the facade of the building in a similar fashion the back represent everything behind the building contrary to Paris we separated the front and the back to a low level easier to switch front and back independently because you could have a very nice representation of the street side but you want to change the parkour situation on the back by changing the type of staff you have at the back so you could change the front or the back independently the roof was the last in deep it indispensable parts to complete the building the basement and found it unfortunately not very visible here could be added automatically if the building is in a slope so if one side of the building is not at the same level as

the other side the garden could be added in front to increase the space between sidewalk and buildings we also use did garden for of them what and finnaly the park apart since it will not be an affected game without traversal we had reusable preset pub group used for parkour navigation and hood alongside the facade breeding paths are dependent one to another and this meant if we change one part or the dependent part we also change for example if you try to add an extra floor on the front you will have to change the back to add this extra floor these back could be a different depth so you ended up change in the roof and so on and so forth in some cases the building could be a path through building with open window in front and in the back control it was

a regular building the front part also contains the back information and you can see the hole in the window and doors we had no editable back to ensure that building the wall inside will always fit all the interior wall are in a separate part I will remove the world to see the interior a separate part and we the data interpret and the props are told in a different part that all with a given interior wall part to have different population the props part also contains NPC placement inside the building and the roof similar of the rig for regular buildings and we of course have also all other paths garden basement and Paco and the last

type of part combination is the back alley in order to we play some back alley from building by bukhari here you can see building and now I can replace it by a back alley the tool will automatically generates the ground between the two buildings to fill the gap and you could add a building overpass as an option the building are built using small modules we have to type two main type of modules the first of a three meter wide module used for important piece of the building windows Dorf a with features you can stack some modules one on top of the other to create different floors the second main type of module Arthur Collins half a meter wide you can have as many columns

as you want with a little bit of imagination the facade of the building is taking shape and for some specific module for a feature of the building we had wider modules always multiple of three in this case 6 meters and street level store are built using the same technique the same solution so 3 meter of modules and Collins but with another design and if you add decals and color on each side you have a pretty nice reusable building it's a combination of 3 media modules and health emitter currents here interview you can create your first 3 meter wide building but however if you put the color on the other side of the wall you can create a

4 meter wide building and if we apply the same solution using 2 emoji module 3 meter wide modules you will get a 6 & 7 for obvious time and budget constraint we were looking at posture I generate some part essentially is a very tedious and look relativity one like the basements thanks to a very strict naming convention for each module we were able to extract its exact location in the building and its exact purpose for example here we have a house original house B stands for Victorian one F stands for D F and for door and one for variation by creating a basement path using a matching naming convention we are able to generate all the basement around the city you can see the name

equation is the same the only one F is replaced by 0 F in London the front of the building are from devious architectural style but the back all shares the Victorian style since that interesting fact is working on our advantage it made sense to increase to find a solution to share the back part Swan London and find a generation solution for each back building we created a polished and single template and template is done cloned and adapt to each architectural style in London you have to to type of of Georgian back you have the yellow one and the red one just by changing the color just by sending the module using the naming convention to all our modules we were able to generate backs for hoser the oath of Georgian side is the right one and if we

add a kind of small item on the top you can see we can increase the side of the building in case this was used in the case of neoclassical building wall a little bit taller than the Georgian one and we use the same generation process for the roof in the shed because they share only four different shape throughout London to conclude on the building part with this module solution we could produce a lot of building for less of function cost which all the power generation solution we were able to save time increased initiative is a number of back hoof and basement we are able to create smaller working with smaller modules that easy replaced reproduce copy fixed it's a much easier way to work and module offer a great separation for taking a match edge of the outline

standing now let me know how the building are built it's time to explain how they are placed along the street and how we are able to fit any lengths and any angle the London London is split in seven district each having is own active artistic the action thus to support this action we created seven data bank one data bank for each district and each data bank of team contains three building style for example if we take City of London we have close to free style we have inside we also called the style it as a Victorian one the judge and one and the neoclassical one all district are limited to only three building style out of the seven we have in the game from my conception purposes the stuff London district ended up

containing two a little bit knowledge one World Trade building and it with more than 80 corner buildings across this type building a split in different sizes here we are going to explore the Victorian kit we started by creating the straight building in seven different sizes 3 4 6 7 10 13 16 and 5 different height 2 3 4 5 and 6 floors and we also created all the corner between 30 degrees to 270 in ten degree increment a kid can hold more than one building for each type but can also not hold a building for each type so you can have multiple building in for example the Victorian kit has 3 7 meter wide to floor height building but

had no 10 meter while wide to flow high building so each kid can contain more or less buildings building our place next one next to the other that mean that the given the available width of building 4 3 4 6 7 etc we could only result in 3 in street lengths in integral the same way it was in Paris since we needed to be able to create Street from any lengths we introduced the concept of adjustable building only one per frontage I'm going to talk about it in the next slide and the frontage describe the group of buildings of a one side of the street when the user when the user wrist size a street I try to keep as many existing building as possible so if you reduce the street from 3 or 4 meters we are

going to remove a 10 meter Victorian building and try to reinsert a 6 meter Victorian building to keep the street earth consistent opposed as possible let's focus on the adjustable building that you see me is capable to assume any size between 3 and 4 meters let's check out a small video look at the building with the light green cylinder in front in his side is going to shrink until it reach under 3 meters in fact the building is split in three four in three subgroups one for each side containing the currents and the world perpendicular to the street and a central group containing the rift we slide the subgroup into the free meter Center to which all the thighs between 3 & 4 so if we take a graphical

representation of all the street lengths we could build if we add the building we have at the beginning 4 3 4 6 7 etc we ended up with this side of this kind of treatment could create if you had all the combination of buildings we can create almost everything around 9 meters and if we add one adjustable building in each frontage we were able to create everything between 3 and 4 meters everything between 6 & 8 and everything over 9 meters in order to our street at any angle we had to have corner buildings capable to match any angle to generate the the general concept between adjusting building to an angle is to rotate the wall around six people points here you can see a 90 degree building in

top view and the 6000 points are located here we use only rotation on the building no scaling in order to avoid creating unique geometry for each corner since we already have created building for each corner in 10 degree increments we needed only a rotation of priests or -5 degrees we thought that such a minor deformation will not be noticeable only the roof needed to have unique geometry the geometry is generated deforming a template and the coefficient the coefficient decrease with altitude in order to keep the off ridge so let's check out the origin of the deformation together here is a screenshot of the back of 90 degree building at first I want the gray

deformation remember the top view from the previous slide they went away is between this world and this world let's continue our journey two degrees three four five at this point it's pretty clear we cannot use this solution in anthropology the result makes no sense nobody will build a building with window that close to each other and if we look at other part of the the roof in front doesn't look that bad with a 5 degree deformation but the back is pretty much destroyed and even the current are stretched too much so we had to find another solution we concluded that it was not possible to have an adjustment of plus or minus 5 degrees on the corner building alone so we decided to split

the load in three buildings the corner and the two building adjacent the corner to the gray on each building edges in the corner and one on the corner itself the corner billing is alas to be alternated in order to avoid generating roof geometry as much as possible if we look at a building next to the corner he split in three parts like the adjustable building and instead of just lighting the world inside and out we just rotate the wall next to the build just in corner and he's going to adjust to the angle correctly to conclude on the building placement I'm going to bring back the diagram from for flight ago with the introduction of the angle solution we had new limitation we needed a minimum of three buildings along a street one next

to each corner to account for the angular deformation and one in the center to account for the fractal part of the street lengths so everything and there are nine meters was not possible anymore to sum up we have we ended up having to build much more building adjustable as the free meter we originally intended to create because it looked where to always have free meter buildings next to corners so we ended up having to create limit adjustable buildings not only for the free meter like we originally intended but also for for freaks 7 10 13 I think we don't create a D 16 and this building are 30% more expensive to create because you have subgroup to manage and and kind of

stuff in hope in order to have 9 meters between corners we had because 9 meters is now there are minimum three things we can create now we had to produce smaller corner building in order to try to give to crop some side of the of the corner so we ended up creating more smaller cone and at this point you are probably asking yourself was it worth it all this job placing building next to the street was definitely worth was it for our project we had early playable buildings we called why very early in production and the city was ready sooner as any other event hit game before but definitely there is a lot of room for improvement let's continue in the props and card life we placed throughout London in addition of the park wall group do a member from the beginning we needed to be able to

add props in front of buildings to create some Paco rode off simply to add some variety we reused the modular structure of the building in order to add magnets at some key modules now you can see in the picture this current is for art form and yet on it at this point you probably wondering why is occurring that man yet - tuition was originally created for the highway bridge to snap two segments of bridge together to avoid gaps between the segment for the overpass you have a small video about that it's very short be aware up snapped in in addition of the magnet on the building we added magnet on the tops we very early discovered that we had to filter

everything because when we added magnet on honing and we didn't filter it we we didn't have owning only on top of store we had earning everywhere so filtering is key the first implementation of the magnet solution was for the user to select any time and try to drag it along the wall until it snaps somewhere it was very similar that the solution we used for bridges but we quickly hide that it was not a good solution we had to make new magnets one close to another and the placement was very tedious we switched to displayed all the available slot on the wall and just by selecting one a list of all the compatible pops will be displayed and you will have a good tool wherever you want and move to the next the list is always curated depending of

the flags on the props and ETM you want to place for the chimney we use the same magnetic solution with specific tags of course and as you can see we had some Sriman a variety innovation we originally intended to have cascading man yet for chimney one for slapping the shinde wall on top of the roof and on this wall we would have awesome a net to snap to snap the silly exhaust on the top of the wall but after using the man yet we arrived that it was not that it was sufficient to have only one snap man yet for the chimneys so we didn't do cascading magnet but he would be fun and the cord life is a big part of the a fun-filled expand the creditor living bringing world feeling throughout the city called life is made

up of station like a guide reading his newspaper to people talking about the weather placed throughout the city in order to ensure proper station placement we created slots for cold station at ground level the new garage was very similar as pop man yet the sweet question tool automatically generated a first path of car life when the building are built and as you can see the idea is the same you have slots they are much bigger because car life is much bigger but it's the same ID you have slots you have lists you select another whole life and you can cycle between all the car life the main feedback we received on the building pops is that it was available too late in production the post-mortem revealed that it was a really efficient way to add items on wall and off it on collage diversity scene since all the

available props are clearly displayed on previous a solid game because of the difficulty to find pops level designer tend to reuse as they new instead of even if more were produced called life slot ended up not being used that much not because of the implementation but because of the restriction imposed by the 5 of the side wall we did not have enough space on sidewall to add a lot of car life many station and the rep in location not covered by the whole network parks back alleys and this kind of term as you can see in this design document as you can see in this design document street lamp and lamppost our first part of the game early on it

was one of the last feature we implemented in the whole network pipeline side wall pops are generated based on old holes are defined ones and use multiple times throughout the city the holes are very simple parameters if we start from an empty street we could use a rule to add ball outs next to the street we props will be play every pub will be placed directly on the sidewalk we also could alternate between two props in this case I added from lamppost the ratio the ratio doesn't need to be one-to-one we could have to balance between each lamppost but as you can see here already as you after stick the act all going to tell you finishing a street with a ball out is not very pretty so we quickly arrived that enforcing strictly

the space between 12 is not very important it's a fact and starting and finishing with one specific pub is more important so we ended up having kind of an auto scaling roof that try to have a lamppost at the start in the beginning the lamppost is defined by the rule the rule could also be placed next to the building or in the center of the street and of course you can adjust density and the endpoint of each side the first bottom highlighted that the bigger challenge we faced was the whole description a lot of level designer needed to use a whole ones to look what the result to really understand what it did this was noticeable in wolf placing props on both side of the street in an alternating pattern we also did not have a proper solution for attempt placed only once

like mailboxes we ended up putting a big value in the distance between field of the walls we also made the mistake to not strongly enforce the rules to have only destructible object in it and we ended up having indestructible object on sidewalks it was fixed later but at the end it was a big success because we ended up placing a little bit less that eight thousand props throughout London with this tradition the user interface is the last section of the talk is a journey through the evolution of the user interface during the project the user interface was designed in two parts first was the 3d orientation we decided to use a lot of debug display to a present editable all the indictable

information starting by the street here is a picture in this picture we can easily recognize the street a street is a group of edge that share the same color a street share of the same configuration like pavement style and width each Street can be named and leveled in our shoes to use the real name of the street in London if we zoom a little bit further the stars are cutting a new street they are new building placed on the frontage but the orientation is what will be present if you select the frontage it highlighted in yellow and then an orange and yellow sphere appear this fair are used to offset the construction along the frontage with using the offset we could expand of a strict building placement alongside the

frontage it was very useful in case we didn't have any corner building or we wanted to fill empty space with trade building we choose to color instead of left and white offset because it was less confusing when building are generated the frontage is split in two lots each rod hold only one building with an in alternation between green and dark green the only light will not focus on the adjustable building and mentioned previously please look at the first lot when the usual select a lot he was able to do very simple operation like splitting or merging some rods in this case I'm going to split this lot in three smaller Lots so just an action pressing one key on the keyboard and of course you can convert into back alleys karate to open building you can do every

operation just by selecting one plot and one smaller section is highlighted in yellow the props or the popped holes are displayed on front edge - they have their own documentation each slot has a smaller foundation and you can select it to remove it in case it's in front of back alley entry for example since the world goal of this project was to have traffic homing throughout the beautiful city we had to find a way to account and edit his flow we chose to use common orientation of course work and our even if the Estonian was pretty pretty scared by that because because it was not used during the Victorian area but it was very easy to grasp for the well designer

the cost work will be moved along the edge from this original position so you could move the location where the people are going to cross the street and to avoid any traffic jam we could configure every lane in only one or multiple direction for changing building paths we started from what was developed on AC unity we used the cycling world to describe the action of changing buildings from one part to another the process on unity was very simple you use your mouse to click to the path we wanted to change the roof of the body for example and you press up and down on your keyboard to change between the relation it's called cycling for this reason to improve on that we decided to focus on load instead of

building parts by rolling all the paths to be changed in in by only selecting one load when a lot was selected we had a cycler appearing on the top left of the screen and for the type of path we want to cycle and a cycler for the value on the right top side of the screen to side between all the value so this time the level designer could know you what part is coming next and each cycling will clearly contains a key you have to press and you are no longer need to use your mouse to change between parts you probably remember this dependency graph from a cover slide ago it indicate dependency between the three major parts if you change one the other part also depending paths are going to change if we look at this simple case it's a Victorian house we flowe angle

roof and if you want to keep the same parameters but try to convert it into a Georgian one we would have to cycle the front as soon as that happened all the other part will also change this will weathered in 15 women designer and a pretty destructive process in order to address this problem we introduced a new cycling mode not likely related to a specific path but multiple concept the concept of style it allowed the user to change the style without having to cycle throughout every part so it just turned aside once and the phone's the back and the roof are going to change we also applied the same concept to the floor height but at this point we realized that the cycling was not the proper solution we needed we needed to be able to go from one point in relief to another without having to

pass throughout every buildings in every item in the way and needlessly altering stuff in the way the Caddy is the solution we finally settled on it was a floating panel that appeared on the right whatever you select in the 3d orientation the caddock always contains custom-made UI for the situation here are some example the first is a street configuration because we only had a limited number of treat width we had to provide a simple way to edit the total which is calculating the point the ponding of the parameter provided by the level designer the second is the cord life slot the felt is caddy for lots in basement configuration the top part for

these four general configuration that type the style the number of floors you are going to have the bottom is for basement configuration specifically the fourth is for building props here we use the thumbnail view it on collage variety by preventing all the props in a simple and understandable way and the last similar to the firm but this time in front of Eurasian the top is the same you have style so on and so forth but button displays all the thumbnail for the building part to allow the user to move quickly from one to another and once more had the interesting side effect on quality the city because everything was clearly displayed the first thing we learned is that in order to have read 3d view we absolutely need performance we did a bug display we ended up having to having to

do a lot of optimization in 3d display on during and peeking I cannot emphasize enough how important it is being able to render in 3d open the new field in you expose abilities and will as probably all for the majority of the game editor which is really property grid based but the Caddy with its custom UI tailored to every face specific job was the most praised feature of the post-mortem usual asking of this kind of edition in other part of envy so takeaways a whole generation is not enough if you create a theory system consider generating the entire ground not only the street it's riveted in a lot of time spent in back and forth between artists would wind the ground and level designer will

move the street around so consider building generating everything one of the biggest success is the possibility to drive in the game very early on even if the old world grey flat we were able to test and improve the game London was the first city in all the brain front story to be played as early in production we think that is a major ingredient of the success of our first Assassin's Creed but Quebec modular building are suitable solution in our however I personally think we didn't push the boundary enough we should assemble all the building by curd not by hand and we would have it was a major of time-consuming for the project and last custom you I have a way to go the post-mortem revealed that custom UI that suits needs of each clef of user of

level designer level artist with your designer and all the classes you could have built with a combination of clickable 3d elements and custom design panel tailor for each job is the way to go every game editor has a property grid to edit complex object but please not underestimate the gain of carefully design user interface thank you and if you have any question feel free to use Mike's send me a mail and I will be tomorrow but piece of lounge from 11th to 12th [Applause] [Music] [Applause] yes hello I have a question about

optimizations of these like generated buildings and cities how did you dealt with the level of details like lot these kind of things look the question is about how we optimize the modules we used sampling on for the majority of the job the el-oued a 1 and a 2 we used some people hi thank you for the talk was great I was wondering when you were talking about the placement like of the lots what about the depth and like the like negative space that it's great because like of the depth of the buildings how do you manage that actual part of the placement of buildings behind the building yeah behind of the negative space like the empty space that means that the Puft was done by so the question is about what we do behind the building so that did the part with generated by hand that's that part of the problem thank you

thank you [Applause]